1. Field of the Invention
The present invention relates to a sealing glass composition. More particularly, the present invention relates to a sealing glass compositon which comprises low-melting glass powder, ceramics powder having a low-thermal expansion coefficient and solid solution powder. The sealing glass composition is useful particularly for sealing an alumina package for an electronic component such as a semiconductor integrated circuit (hereinafter referred to simply as "IC").
2. Description of the Prior Art
For the sealing of an alumina package for IC, there has been used a composition comprising low-melting glass powder containing PbO as the major component, and ceramics powder having a low-thermal expansion coefficient, such as zircon, cordierite or lead titanate. However, the sealing compositon containing cordierite or lead titanate as the ceramics powder, has poor sealing strength and is not suitable for sealing a large size package for a large size IC which has become common in recent years as a result of development of highly integrated circuits. On the other hand, the sealing composition containing zircon as the ceramics powder, has adequate sealing strength but it has a drawback such that the impurities contained in zircon emit a substantial amount of .alpha.-particles, which tend to lead to soft errors of the IC.